4,4-bis (difluoramino)-1,7-difluoro-1,1,7,7-tetranitroheptane

ABSTRACT

4,4-bis (difluoramino)-1,7-difluoro-1,1,7,7-tetranitroheptane, a plasticizer for double-base propellant systems, is synthesized by reacting 1,7-difluoro-1,1,7,7-tetranitro-4-heptanone with a mixture of fuming H2SO4, CH2Cl2 and HNF2.

write States Patent Coon et al. 51 Jan. 30, 1973 [54] 4,4-BIS(DIFLUORAMlNO)-1,7- [56] References Cited DIFLU R -l 1 7 7- g g dfi gUNITED STATES PATENTS [75] Inventors: C f Lt b Fremont; a 3,470,1709/1969 Dinwoodie et al. ..260/244 E. Hill, Palo Alto; Donald L. Ross,Menlo Park all of Calif. Primary ExammerLeland A. SebastianAttorney-Richard S. Sciascia, Q. Baxter Warner and [73] Assignee: TheUnited States of America as Gayward N, M

represented by the Secretary of the y 57 ABSTRACT v Filed: 13,19694,4-bis (difluoramino)-l,7-difluoro-l,l,7,7- [211 App]. No: 866,438tetranitroheptane, a plasticizer for double-base propellant systems, issynthesized by reacting 1,7difluoro- 1,1,7,7-tetranitro-4-heptan0ne witha mixture of fum- [52] US. Cl. ..260/583 NH, 149/88 ing H280h CHZCI2 andHNF2 [51] Int. Cl ..C07c 87/22 [58] Field of Search ..260/5 83 NH 3Claims, N0 Drawings 4,4-BIS (DIFLUORAMINO)-l,7-DIFLUORO-l,1,7,7-TETRANITROHEPTANE STATEM ENT OF GOVERNMENT INTEREST The inventiondescribed herein may be manufactured and used by or for the Governmentof the United States of America for governmental purposes without thepayment of any royalties thereon or therefor.

BACKGROUND OF THE INVENTION 1. Field of the Invention This inventionrelates in general to novel chemical compositions and in particular tocomplex fluoronitro compounds useful as plasticizers for double-basepropellants and to a method of making the same.

2. Description of the Prior Art Many prior additives have beenincorporated into double-base propellant systems in order to upgrade thepropellants by increasing the specific impulse, burning rate, etc. Butmost added ingredients are unsatisfactory in that they do not meet allrequirements necessary for their use in the system. The presentplasticizer composition, however, may be incorporated into allpropellant systems for upgrading purposes without any deleterious sideeffects. It will meet and satisfy all plasticizer requirements for usein any double-base propellant.

SUMMARY OF THE INVENTION This invention concerns a novel plasticizercomposition for incorporation into a double-base propellant system orother explosive compositions. It will upgrade such systems by increasingthe specific impulse and burning rate of the propellants. Specificallythe novel plasticizer is 4,4-bis (difluoramino)-l,7-difluoro-1,l,7,7-tetranitroheptane and is synthesized by reactingl,7-difluoro-l,l,7,7-tetranitro-4-heptanone with a mixture of thefollowing ingredients: fuming H SO ,CH 2 cl and HNF OBJECTS OF THEINVENTION It is an object of the present invention to provide animproved plasticizer composition for use in doublebase propellantsystems.

It is another object of the present invention to provide an improveddouble-base propellant plasticizer which is easily synthesized by asimple and direct reaction series.

It is a further object to provide an improved plasticizer compositionwhich will plasticize nitrocellulose, is compatible with double-baseingredients, is heat stable, has a high density, has a low vaporpressure, has a high heat of formation and will increase specificimpulse ofa propellant.

It is a still further object to provide an improved plasticizercomposition for double-base propellant systems which is economical tosynthesize and reliable in operation.

Other objects, advantages, and novel features of the invention willbecome apparent from the following detailed description.

DESCRIPTION OF THE PREFERRED EMBODIMENT This invention comprises a newplasticizer for double-base propellant systems comprising 4,4-bis(difluoramino)-1,7-difluoro-l,l,7,7-tetranitroheptane formed by thefollowing chemical synthesis:

OCH:

The following example serves to illustrate the present invention. Itwill be noted that the preparation of the present compound starts withl,7-difluoro-1,1,7,7- tetranitro-4-heptanone and for the synthesisthereof refer to M. Graff and W. H. Gilligan, Journal Organic Chemistry,33, 1247 (1968).

EXAMPLE To a mixture of 29 ml. of 30 percent fuming H SO and 25 ml. ofCI-I CI at 5C was condensed 9.66 g (0.18 mole) of HNF To this mixturewas added a solution of 14.8 g (0.045 mole) of l,7-difluoro-1,l,7,7-tetranitro-4-heptanone in ml. of CH Cl- The reaction mixture was stirredat 05C for 15 minutes and the organic phase and the acid phase werepoured into separate beakers of crushed ice. The organic phase wasseparated, washed thoroughly with water, and dried over magnesiumsulfate. The CH Cl was evaporated leaving 14.2 g. (76 percent yield) ofpale yellow solid 4,4-bis (difluoramino)-l,7-difluoro-l,1,7,7-tetranitroheptane.

This novel heptane has a primary purpose as a plasticizer fordouble-base propellant systems. It is a solid compound with a meltingpoint of 53.5 to 555C and is insensitive to a hammer blow. It willplasticize nitrocellulose, is compatible with double-base ingredients,is heat stable, has a high density, has low vapor pressure, has highheat of formation, will increase specific impulse and burning rate ofthe propellant and is easily synthesized. In addition this com pound isalso useful as an ingredient in explosive compositions.

We claim:

1. The composition 4,4-bis (difluoramino)-1,7-difluoro-1,l,7,7-tetranitroheptane having the formula:

2. The process of synthesizing 4,4-bis(difluoramino)-1,7-difluoro-l,1,7,7-tetranitroheptane comprisingreacting 1,7-difluoro-1 ,1 ,7,7-tetranitro-4- heptanone with a mixtureof fuming H 80 Cl-l cl and tetranitro-4-heptanone was added to saidmixture comprising 29 milliliters of 30 percent fuming H 25 millilitersof Cl-l Cl and 9.6 grams of HNF UNITED STATES PATENT @FFECE m Tmm'm -F@EQ'HQN Patent-N0. 3,714,260

Dated 30 January 1973 Invent fls) Clifford L. Coon etal It is certifiedthat error appears inTt-he aboveidentified patent and that said LettersPatent are hereby corrected 'as shown below:

Column 2, line 62, that portion- 0 f formula reading CH CH' should readCH CH 2 1 a Sig'nedand sealed this 10th da of July 1973.-

(SEAL) Attest:

EDWARD 'M.FLETCHER-,JR. Rene .Te gtmeyer 'Attesting Officer ActingCommissioner of Patents FORM PO-1050 (10-69) USCOMM-DC 603764 69 mnueOFFICE I969 o-ss5-334 w u.s. eovsmmsm' Pk UNITED STATES PAifEN QFMQEQE'RTH'NIATE F (BURKECTEGN Patent No. 3,714, 260 Dated 30 Jahuary 1973lnv fls) Clifford L. Coon et al It is certified that error eppearsin'fthe and that said Letters Patentare hereby correct ehe ve identifiedpatent eclas shown below:

Column 2, line 62, that portion '0 v f formula reading CH CH should readCH CH2] 2 Sig'nedend seemed this 10th da of July 1973,

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ReneTe'gtmeyer Attesting Officer ActingCommissioner of Patents FORM PO-105O (10-69) v UsCOMM-DC 60376-P69 wuvs. GOVERNMENT PRINTING orncs; was 0-366-334

1. The composition 4,4-bis(difluoramino)-1,7-difluoro-1,1,7,7-tetranitroheptane having theformula: (FC(NO2)2CH2CH2)2C(NF2)2
 2. The process of synthesizing 4,4-bis(difluoramino)-1,7-difluoro-1,1,7,7-tetranitroheptane comprisingreacting 1,7-difluoro-1,1,7,7-tetranitro-4-heptanone with a mixture offuming H2SO4, CH2Cl2 and HNF2, said process being carried out at atemperature between about 0*-5* C.